Cognex Corporation · NASDAQ:CGNX

Cognex — Technical Presentation (2019)

47 slides from Cognex's technical presentation, 2019

Slide 1: Understanding Verification Results
UNDERSTANDING VERIFICATION RESULTS A deeper look at what the software is telling you. 2019 1 © 2019 Cognex Confidential
Slide 2: Why am I getting a no decode when the code can be read?
WHY AM I GETTING A NO DECODE WHEN THE CODE CAN BE READ USING ONE OF OUR READERS? 2 © 2019 Cognex Confidential
Slide 3: Additional reasons for a no decode
ADDITIONAL REASONS FOR A NO DECODE  Are you using the correct aperture?  Are you using the right ISO Standard?  Are you using the right lighting angle?  Is the symbology enabled?  Is the camera in focus?  Is the code in the center of the FOV?  Is the code close to perpendicular?  Do the cell
Slide 4: Why would my grade fluctuate from one letter to another?
WHY WOULD MY GRADE FLUCTUATE FROM ONE LETTER TO ANOTHER? 4 © 2019 Cognex Confidential
Slide 7: Barcode ISO Standards
BARCODE ISO STANDARDS These standards spell out the guidelines for creating, decoding, error correction, encodation, etc. BARCODE TYPE ISO STANDARD DATA MATRIX ISO/IEC 16022 QR CODES ISO/IEC 18004 AZTEC ISO/IEC 24778 UPC/EAN ISO/IEC 15420 CODE 128 ISO/IEC 15417 CODE 39 ISO/IEC 16388 PDF 417 ISO/IEC
Slide 8: Barcode Quality Grading ISO Standards
BARCODE QUALITY GRADING ISO STANDARDS Barcode Type 1 2 3 4 5 6 7 8 9 0 1D (Linear) 2D Marked Substrate Label Label Direct- Part-Mark (DPM) ISO IEC TR 29158 Standard ISO 15416 ISO 15415 (also called AIM-DPM) 8 © 2019 Cognex Confidential
Slide 9: ISO/IEC 15415 (2D printed on flat labels)
ISO/IEC 15415 (2D printed on flat labels) 9 © 2019 Cognex Confidential
Slide 10: 29158 vs 15415?
29158 vs 15415?  Global threshold calculatation: Calculated differently so image appears brighter.  Modulation grading levels: Modulation is calculated differently to accommodate for the variety of different surfaces codes are printed on.  Allowed lighting angles: 30-degree, 45-degree, 90-degree
Slide 11: Application Standards
APPLICATION STANDARDS – Industry guidelines to be used along with ISO standards Tip – a useful way to think about Application Standards: specification of type of barcode to use (DataMatrix etc.) and format of the data, and how to implement the ISO grading standard. Defense Medical Devices Retail/ Ph
Slide 13: Reference Decode Algorithm Process
REFERENCE DECODE ALGORITHM PROCESS 1. Blur image 2. Calculate Global Threshold 3. Convert to binary black and white image 4. Trace lines to find L pattern 5. Search for clock tracks 6. Calculate grid spacing 7. Sample at grid intersections for average reflectivity within each aperture 8. Apply Reed-
Slide 21: Setting Selections
SETTING SELECTIONS Is the correct application standard selected? Is the correct ISO standard selected? Is Dot Peen Is the correct selected? aperture selected? Is the code size within the x-dimension range? 21 © 2019 Cognex Confidential
Slide 22: "Stick Algorithm"
“STICK ALGORITHM” • Dot Peen symbols do not contain continuous edges • Consequently the decode algorithm for Data Matrix fails on dot peen symbols • Rather than change the symbology specification, change the image by “connecting the dots” • Fill in the “stick” whenever both ends are on color 22 © 20
Slide 24: Aperture
APERTURE  A circular group of pixels is averaged together  A blur is applied to “smooth” the image  The blur also removes “texture”, dirt, printing imperfections  The blur also limits resolution 24 © 2019 Cognex Confidential
Slide 25: Aperture Effect
APERTURE EFFECT Aperture all on Aperture all on black white Aperture all on white 25 © 2019 Cognex Confidential
Slide 39: Unused Error Correction
UNUSED ERROR CORRECTION  Any grades showing the use of error correction indicate that the code needs work.  It is an indication that there are module(s) that are calculated as being the wrong color.  Review the advanced detail tab and look for modules listed as a zero value and evaluate why they
Slide 40: Cell Contrast / Symbol Contrast
CELL CONTRAST (ISO/IEC TR 29158 AIM DPM)  The relative contrast value between bars and spaces, taken from the means of the light and dark element. (CC=(Lmean-Dmean)/Lmean)) SYMBOL CONTRAST (ISO/IEC 15415)  This is a measure of overall contrast between the brightest module and the darkest module. 4
Slide 41: Modulation & Reflectance Margin
MODULATION & REFLECTANCE MARGIN  Modulation is a measure of localized contrast issues  Can be caused by textures or imperfections in the substrate, defects in the mark or bar width growth (BWG)  To reduce BWG you can adjust the amount of ink used, the speed or temperature of the marking process o
Slide 42: ANU & GNU
ANU & GNU AXIAL NON-UNIFORMITY (ANU) GRID NON-UNIFORMITY (GNU)  When module grid alignment is not centered based on the calculated grid  The amount of “out of square” a symbol is or in  The grade is determined by other words a measure the worst case distance of the overall aspect between the calc
Slide 43: Fixed Pattern Damage
FIXED PATTERN DAMAGE Caused by modulation or wrong colored modules in the finder pattern. Fixed Pattern • L Pattern • Clock teeth • Quiet Zone 43 © 2019 Cognex Confidential
Slide 44: Decode
DECODE Can it be decoded using the selected aperture applied with the standard reference decode algorithm? Yes No 44 © 2019 Cognex Confidential
Slide 45: Minimum Reflectance
MINIMUM REFLECTANCE Good Bad • The measure of how light or dark the part is before it is lightened by the image adjustment of AIM DPM • If the brightness level is less than 5% before the AIM DPM image adjustment takes place it will fail. 45 © 2019 Cognex Confidential
Slide 46: Conclusion
CONCLUSION  Try not to get overwhelmed trying to learn everything about verification. Take it one step at a time and remember the basics.  It’s all about having crisp definition between dark and light modules and a clean finder pattern.  If the code looks blurry, has poor contrast or is missing m
Slide 47: For more information on barcode verification visit www.cognex.com
For more information on barcode verification visit www.cognex.com 47 © 2019 Cognex Confidential

Cognex — Technical Presentation (2019) on 6ix

Cognex — Technical Presentation (2019)

Slide 1: Understanding Verification Results

Slide 2: Why am I getting a no decode when the code can be read?

Slide 3: Additional reasons for a no decode

Slide 4: Why would my grade fluctuate from one letter to another?

Slide 5: Why am I getting an F?

Slide 6: ISO Standard Overview

Slide 7: Barcode ISO Standards

Slide 8: Barcode Quality Grading ISO Standards

Slide 9: ISO/IEC 15415 (2D printed on flat labels)

Slide 10: 29158 vs 15415?

Slide 11: Application Standards

Slide 12: How is a Data Matrix decoded?

Slide 13: Reference Decode Algorithm Process

Slide 14: Original Image

Slide 15: Blurred Image

Slide 16: Binary (B&W) Image

Slide 17: Image with Defects

Slide 18: Blurred Image

Slide 19: Binary (B&W) Image

Slide 20: Verifier set up for your application

Slide 21: Setting Selections

Slide 22: "Stick Algorithm"

Slide 23: Algorithm to Connect Dots

Slide 24: Aperture

Slide 25: Aperture Effect

Slide 26: Aperture Size

Slide 27: Example Verification Process

Slide 28: Place the code in the center of the FOV

Slide 29: Results at first glance

Slide 30: What are the dots saying?

Slide 31: The cell is in the gray area

Slide 32: Modulation

Slide 33: General Characteristics Tab

Slide 34: Data Detail Tab

Slide 35: Quality Detail Tab

Slide 36: Histogram Tab

Slide 37: Report Tab

Slide 38: Explanation of Quality Parameters

Slide 39: Unused Error Correction

Slide 40: Cell Contrast / Symbol Contrast

Slide 41: Modulation & Reflectance Margin

Slide 42: ANU & GNU

Slide 43: Fixed Pattern Damage

Slide 44: Decode

Slide 45: Minimum Reflectance

Slide 46: Conclusion

Slide 47: For more information on barcode verification visit www.cognex.com